On Thu, Aug 09, 2012 at 12:07:36PM +0200, Thomas Renninger wrote:
> On Tuesday 07 August 2012 04:24:48 Palmer Cox wrote:
> > The pkgs member of cpupower_topology is being used as the number of
> > cpu packages. As the comment in get_cpu_topology notes, the package ids
> > are not guaranteed to be contiguous. So, simply setting pkgs to the value
> > of the highest physical_package_id doesn't actually provide a count of
> > the number of cpu packages. Instead, calculate pkgs by setting it to
> > the number of distinct physical_packge_id values which is pretty easy
> > to do after the core_info structs are sorted. Calculating pkgs this
> > way also has the nice benefit of getting rid of a sign comparison warning
> > that GCC 4.6 was reporting.
> > ---
> > tools/power/cpupower/utils/helpers/topology.c | 18 +++++++++++++-----
> > 1 file changed, 13 insertions(+), 5 deletions(-)
> >
> > diff --git a/tools/power/cpupower/utils/helpers/topology.c
> > b/tools/power/cpupower/utils/helpers/topology.c
> > index 4e2b583..fd3cc4d 100644
> > --- a/tools/power/cpupower/utils/helpers/topology.c
> > +++ b/tools/power/cpupower/utils/helpers/topology.c
> > @@ -64,7 +64,7 @@ static int __compare(const void *t1, const void *t2)
> > */
> > int get_cpu_topology(struct cpupower_topology *cpu_top)
> > {
> > - int cpu, cpus = sysconf(_SC_NPROCESSORS_CONF);
> > + int cpu, last_pkg, cpus = sysconf(_SC_NPROCESSORS_CONF);
> >
> > cpu_top->core_info = malloc(sizeof(struct cpuid_core_info) * cpus);
> > if (cpu_top->core_info == NULL)
> > @@ -78,20 +78,28 @@ int get_cpu_topology(struct cpupower_topology *cpu_top)
> > "physical_package_id",
> > &(cpu_top->core_info[cpu].pkg)) < 0)
> > return -1;
> > - if ((int)cpu_top->core_info[cpu].pkg != -1 &&
> > - cpu_top->core_info[cpu].pkg > cpu_top->pkgs)
> > - cpu_top->pkgs = cpu_top->core_info[cpu].pkg;
> > if(sysfs_topology_read_file(
> > cpu,
> > "core_id",
> > &(cpu_top->core_info[cpu].core)) < 0)
> > return -1;
> > }
> > - cpu_top->pkgs++;
> >
> > qsort(cpu_top->core_info, cpus, sizeof(struct cpuid_core_info),
> > __compare);
> >
> > + /* Count the number of distinct pkgs values. This works
> > + becuase the primary sort of of the core_info structs was just
> becuase ... of of ... struct instead of structs
Oof. I'm not winning any grammar medals for this. Thanks for
noticing.
>
> Otherwise the first 4 patches look like rather nice and straight forward
> cleanups/fixes.
> Feel free to add a Reviewed-by: Thomas Renninger <tr...@suse.de>
Will do. Thanks!
>
> Let me have a closer look at patch 5 and 6. I had problems getting rid of
> the compiler warning, looks like you found an easy way to clean this up.
> I will be back and have time for this in the beginning of next week.
Thanks for the review! Let me know if there is anything in patches 5
and 6 that needs cleaning up and I'll be happy to do it. I only have
access to a laptop with a single package 2 core Centrino2 processor.
I tested each patch in the series on my laptop running a 64-bit 3.5
kernel to make sure that everything functioned. I'm no expert in the
exact expected output of the tool, but the only impact that I
believe these patches should have is the output of the number of cpu
packages. I tested this on my system which resulted in reporting
just a single cpu package as I expected, but I don't have access to
a system with multiple cpu packages to test on.
>
> On which platforms (topology) did you test this?
>
> Thomas
-Palmer
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